Rivet



Aug. 17,1943. c. E. HATHORN RIVET Filed NOV. 12, 1941 2 Sheets-Sheet l INVENTOR @H4/MEI [.lTl/ORN 'lll/111111114;

'IIIA-PII I l ATTORNEY Aug. 17, 1943.

C. E. HATHORN RIVET Filed Nov. 12, A1941 V 2 SheetsSheet 2 V,

INVENTOR cla/ufr f. H4 T HoR/v ATTO R N EY Patented Aug. 17, 1943 RIVET Charles E. Hathorn,

Kenmore, N. Y., assignor to Curtiss-Wright Corporation, a corporation oi' Delaware Application November 12, 1941, Serial No. 418,670 Claims. (Cl. 85-40) This invention relates to blind rivets and. is concerned with improvements, both in the rivet and in the mode of drivingsame, over the arrangement shown in my Patent No. 2,248,755, issued'July 8, 1941.

In the rivet taught in said patent, an initial internal bulge is formed in the rivet bore and, by drawing av ball-headed mandrel outwardly through the rivet, the internal bulge is transposed to an external bulge which engages the material through which the rivet is inserted. The present invention contemplates the use of substantially the same character of rivet but.' instead of drawing a mandrel outwardly through the rivet, I provide means for securing the rivet `by pressing a core inwardly through the rivet. For a clearer understanding of the details of the invention reference may be made to the attached specication and to the drawings, in

which:

Fig. 1 isa sectional elevation through a rivet according to the invention, including driving means therefor;

Fig. 2 is a section completed Joint;

Fig. 3 is 'a section rangement of a rivet;

Fig. 4 is a section through an alternate arrangement of a rivet;

Fig. 5 is a side elevation of an alternate form of rivet;

Fig. 6 includes a plan and side alternate form of rivet;

'Fie'. 7 is a side elevation a rivet driving core and ing same from a driven Fig. 8 is a combined plan and side elevation of a form of rivet such as that shown in Fig. 1:

Fig. 9 is a disassembled view of a core and rivet assembly;`

Fig. 10 is a fragmentary section core and rivet assembly of Fig. 9;

through a rivet showing a through an alternate arelevation of an partly in section of a mandrel for withdrawrivet;

through the Fig. 11 is a section on the line I I-IIof Fig. 10, v

Fig. 12 is a side elevation of a riveted Joint using the modication of Fig. 9.

All of the several rivet modifications shown in thin in the vicinity of the bares Is and n, and relatively thick drilled opening in work core 2I, having an ogival inner end 22, is forced inwardly, from the external (upper) surface of the work. This core has an external diameter substantially the same as that ,of the bores I6 and Il so that, when it is forced through the small bore I8, the shank material of the rivet is expanded outwardly, forming a bead 23 on the exterior surface of the shank, Awhich binds against the inner surface of the work pieces 20 to hold the rivet ilrmly in position and to secure the work pieces to one another.

Now referring to Fig. 1, I show a driving tool 25 comprising prongs 26 which are engaged with a groove or recess 21, as shown in Fig. 8. Centrally of the tool 25 is a plunger 28 which may` be moved inwardly by squeezing together bellcrank handles 29 having tangs 30 engaging the outer part of the plunger 28. The inner end of the plunger presses against the outer end of the core 2I, as shown in dotted lines, and pushes the core the core is flush with the rivet head. If the protrusion of the rivet head permissible in the work to be accomplished, the tool may merely 'be removed from the rivet and the head left intact. AOn the other hand, if such head pro' trusion is obnoxious. the outer portion of it may be dressed oil to produce the result shown in Fig 2.

Fig. 4 shows a ush rivet having a basic head 34 occupying a countersunk hole in the work pieces 20. The rivet is also providedwith an auxiliary head 35, spaced from In Fig. 5, an auxiliary head 38 takes the form of a screw shank, to be engaged by a nut eleof the driving tool. However, obviously the driving tool 25 of Fig. 1 could be used with the rivet illustrated in Fig. 5, with the tool prongs 26 engaging in the groove 36' below the threaded head 381. In Fig. 3, an oval head rivet in the vkregion of the bore I8. f The rivet is applied through a suitable prepieces 20 whereuponainto the rivet until the outer surface of is shown, y

easier driving of the rivet. That is,

If it is desired to withdraw the driving core from the rivet, the core may be provided with a flanged head 43, as shown in Fig. '7, and a clawhammer or equivalent device indicated at 44 may be used to withdraw the core after the rivet has been driven.

The forms of rivets herein described would be appropriate for production work or repair work where-adequate facilities are available for driving the rivets and dressing their heads. Where field repairs are called for, and where the structure to be riveted is suiiiciently rigid to permit hammer driving of a rivet core 2l, the rivet may take the form shown in Figs. 9 to 12 wherein the shank I5', in addition to the bores I6, II and I8, is formed with a plurality of longitudinal slits 5D, intermediate the length of the shank, and providing openings from the outside of the shank to the bore I8. These slits tend to weaken the bulge in the rivet bore to .permit When the core 2| is assembled as in Fig. l0, said core may be forced inwardly of the rivet by a series of light hammer taps which will force the segmental inward projections of the rivet bore outwardly to provide a riveted joint as shown in Fig. 12. If the core is left inside the rivet, as would normally be the case, strong and is adequate for field repair work.

As in my previous patent above mentioned, the skirt formed at the inner end of the rivet shank serves to prevent fracturing and bursting of the material of the rivet when it is driven, and the bore I8 is preferably tapered at its ends to provide a smooth transition from the large to the small diameter portions of the rivet shank .so as to distribute the stress uniformly in the rivet material.

The rivets herein shown are primarily adapted for light sheet metal work as used in aircraft. Though they may bev made of any material, I contemplate making them of aluminum alloy for aircraft work and the core 2l for rivet driving may likewise be made of an aluminum'alloy somewhat harder than that alloy used in the rivet per se.

While I have vdescribed my invention in detail in its present preferred embodiment, it will be obvious to those skilled in` the art, after understanding my invention, that various changes and modifications may be made therein without del parting from the spirit or in the appended claims to cover all such modiications and changes.

I claim as my invention:

1. A unitary blind rivet comprising a head having recess means for engagement by a driving tool, a shank extending from said head for engagement with sheets to be riveted, said rivet this joint is quite' CTI scope thereof. I aim uponsaid tool may be operated to being hollow and having an inward integral annular protrusion in the rivet hollow, and a core tted to the rivet hollow, protruding from the rivet head, adapted to be pressed into the rivet by said driving tool, to bulge said protrusion outwardly on the rivet shank.

2. A unitary blind rivet comprising ahead, a shank extending from one end of the head, a head extension including a radial recess for engagement by a driving tool, said rivet being hollow, an annular inward protrusion integral with the shank and extending into the rivet hollow, and a driving core fitted to the rivet hollow and protruding outwardly beyond said head extension, whereby the core may be pressed into the rivet hollow by said tool to bulge said protrusion outwardly on the rivet shank.

3. A unitary blind rivet comprising a head, a shank extending from one end of the head, a head extension including a recess, said rivet being hollow, an annular inward protrusion integral with the shank and extending into the rivet hollow, and a driving core fitted to the rivet hollow and protruding outwardly beyond said head extension, said extension comprising a ange adapted to be engaged by a rivet press? ing tool for pressing the core into the rivet hollow to bulge said protrusion outwardly on the rivet shank.

4. A unitary blind rivet comprisingl a head, a shank extending from one end of the head, a head extension including a screw threaded ange portion and a radial recess between said ange and head, said threaded flange and recess each being adapted for engagement by an appropriate driving tool, said rivet being hollow, an annular inward protrusion integral with the shank and extending into the rivet hollow, and a driving core tted to the rivet hollow and protruding outwardly beyond said head extension, whereby the core may be pressed into the rivet hollow by a tool engaging either said threaded flange or said recess to thereby vbulge said protrusion outwardly on the rivet shank.

5. A unitary blind rivet comprising a head portion, a shank portion extending from said head portion for engagement with material to be riveted, said rivetl being hollowand having an inward annular protrusion in the shank portion of the rivet hollow, and a core tted to the rivet hollow, protruding from the rivet head and adapted to be pressed into the rivet to bulgelsaid protrusion outwardly on the rivet shank, said rivet head portion having opposed configurations thereon for intertting engagement with a. driving tool to facilitate alinement therewith, wherepress said core into the rivet.

CHARLES E. I-IA'I'HORN. 

